Hardwoods are used in a variety of applications to provide aesthetically pleasing furniture and flooring. The hardwoods used in making furniture and flooring are susceptible to damage from ordinary usage and accidents. As such, it is conventional to protect hardwoods with some form of permanent coating or finish on their exposed surfaces.
Prior art protective finishes for hardwood furniture and flooring include varnishes, urethanes, epoxies, acrylics, and other suitable coatings that adhere to the surface of the hardwood. The protective finish is usually applied to the hardwood surface in layers, with each layer performing a specific purpose within the coating. For example, the protective finish normally constitutes sealers applied directly to the hardwood surface, and top coat layers applied over the sealing layers. Upon hardening, these multi-layer finishes not only reduce mechanical damage such as scratching, gouging or the like, but also provide stain resistance. Quite often, various layers contain additives to improve the overall effectiveness of the protective finish.
Protective finishes can create a slippery surface on the hardwood. Therefore, with hardwood flooring, it is known to apply a non-slip surface coating to create a high coefficient of friction on the surface. Preferably, the non-slip surface coating does not affect the overall durability or aesthetic qualities of the protective finish.
It is known to use aluminum oxide as an additive in certain layers of the protective finish in order to increase the abrasion resistance. These finishes typically have an abrasion resistance of between 5,000 and 11,000 revolutions when measured using the standardized CS-17 Taber testing procedure (ASTMINEMA Standards).
Many additives that improve abrasion resistance are likely to compromise other desirable characteristics such as clarity, slip resistance, stain resistance, etc. Therefore, it is difficult to develop practical protective finishes with enhanced abrasion resistance. Nonetheless, protective finishes having enhanced abrasion resistance are desirable, especially for use on hardwood flooring.
The invention is a ceramic-based finish for use on hardwood surfaces that has enhanced abrasion resistance. When applied to hardwood flooring, the multi-layered, ceramic-based finish is durable and reduces wear from ordinary usage and accidental damage. In addition, the ceramic-based finish dries clear on hardwood surfaces and allows the grain of the hardwood to show clearly. Also, the finish provides increased stain resistance to normal household substances.
The ceramic-based protective finish is preferably formed by applying multiple layers of sealers (preferably epoxyacrylic or polyurethane acrylic) and top coats (preferably polyurethane acrylic). to the hardwood surface. It should be understood that the term xe2x80x9cepoxyxe2x80x9d as used in this description and in the drawings refers to epoxyacrylic compounds, and the term xe2x80x9cpolyurethanexe2x80x9d refers to polyurethane acrylic compounds. A water-based sealer is preferably applied before applying the multi-layer, ceramic-based protective finish. The sealant layers and top coat layers used in forming the protective finish preferably include the following components:
Epoxyacrylic-oligomers,
urethaneacrylic-oligomers,
hexamethylene diacrylate,
tripropylenglycoldiacrylate,
2-hydroxy-2-methyl-1-phenyl-propan- 1-on benzoyl-derivative,
ethylbenzene,
poly-di-isocyanates
aluminum oxide, and
zirconium oxide.
The above components are combined in water in different formulations to form the various sealant layers and top coat layers. When applied in succession over a hardwood surface and UV hardened, there is optimal bonding both between the base layer and the hardwood surface, and the subsequent layers.
If desired, the multi-layer, ceramic-based coating can be applied over natural or stained surfaces. The ceramic additives (namely, aluminum oxide and zirconium oxide) are included in selected layers. The ceramic additives substantially improve abrasion and stain resistance without compromising clarity or other desirable characteristics of the finish.
It is a primary object of the invention to provide a practical, ceramic-based protective finish that bonds effectively to hardwood surfaces, which also provide improved stain and abrasion resistance.
It is a further object of the invention to provide a ceramic-based protective finish that is easily manufactured and easily applied to hardwood surfaces.
It is a further object of the invention to provide a ceramic-based finish that provides the above advantages, yet is also inexpensive and easy to maintain.